1、UILabel 间隙
NSMutableAttributedString* attrString = [[NSMutableAttributedString alloc] initWithString:label.text];
NSMutableParagraphStyle *style = [[NSMutableParagraphStyle alloc] init];
[style setLineSpacing:20];
[attrString addAttribute:NSParagraphStyleAttributeName value:style range:NSMakeRange(0, label.text.length)];
label.attributedText = attrString;
XIB 设置
XIB 设置 UILabel 间隙
UIlabel 的两端对齐
- (void)textAlignmentLeftAndRightWith:(CGFloat)labelWidth{
if (self.text == nil || self.text.length == 0) {
return;
}
CGSize size = [self.text boundingRectWithSize:CGSizeMake(labelWidth,MAXFLOAT) options:NSStringDrawingUsesLineFragmentOrigin|NSStringDrawingTruncatesLastVisibleLine|NSStringDrawingUsesFontLeading attributes:@{ NSFontAttributeName:self.font } context:nil].size;
NSInteger length = ( self.text.length - 1 );
NSString * lastStr = [self.text substringWithRange:NSMakeRange(self.text.length - 1,1)];
if ([lastStr isEqualToString:@":"] || [lastStr isEqualToString:@"："]) {
length = (self.text.length-2);
}
CGFloat margin = (labelWidth - size.width)/length;
NSNumber *number = [NSNumber numberWithFloat:margin];
NSMutableAttributedString * attribute = [[NSMutableAttributedString alloc]initWithString:self.text];
[attribute addAttribute:NSKernAttributeName value:number range:NSMakeRange(0,length)];
self.attributedText = attribute;
}
识别 html 标签 并添加 行间距， 如过要设置大小，需要再后面加
NSMutableAttributedString *attrStr = [[NSMutableAttributedString alloc] initWithData:[self.svfModel.content dataUsingEncoding:NSUnicodeStringEncoding] options:@{ NSDocumentTypeDocumentAttribute: NSHTMLTextDocumentType } documentAttributes:nil error:nil];
NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle alloc] init];
[paragraphStyle setLineSpacing:5];
[attrStr addAttribute:NSParagraphStyleAttributeName value:paragraphStyle range:NSMakeRange(0, [attrStr length])];
label.attributedText = attrStr;
label.font = [UIFont systemFontOfSize:16];
2、UILabel显示不同颜色字体
NSMutableAttributedString * string = [[NSMutableAttributedString alloc] initWithString:label.text];
[string addAttribute:NSForegroundColorAttributeName value:[UIColor redColor] range:NSMakeRange(0,5)];
[string addAttribute:NSForegroundColorAttributeName value:[UIColor greenColor] range:NSMakeRange(5,6)];
[string addAttribute:NSForegroundColorAttributeName value:[UIColor blueColor] range:NSMakeRange(11,5)];
label.attributedText = string;
3、 performSelector:withObject:withObject:afterDelay:方法时，需要传入多参数问题
// 方法一、// 把参数放进一个数组／字典，直接把数组／字典当成一个参数传过去，具体方法实现的地方再解析这个数组／字典
NSArray * array = [NSArray arrayWithObjects: @"first", @"second", nil];
[self performSelector:@selector(fooFirstInput:) withObject: array afterDelay:15.0];
// 方法二、// 使用
NSInvocationSEL aSelector = NSSelectorFromString(@"doSoming:argument2:");
NSInteger argument1 = 10;
NSString *argument2 = @"argument2";
if([self respondsToSelector:aSelector]) {
NSInvocation *inv = [NSInvocation invocationWithMethodSignature:[self methodSignatureForSelector:aSelector]];
[inv setSelector:aSelector];
[inv setTarget:self];
[inv setArgument:&(argument1) atIndex:2];
[inv setArgument:&(argument2) atIndex:3];
[inv performSelector:@selector(invoke) withObject:nil afterDelay:15.0];
}
4、比较两个NSDate相差多少小时
NSDate* date1 = someDate;
NSDate* date2 = someOtherDate;
NSTimeInterval distanceBetweenDates = [date1 timeIntervalSinceDate:date2];
double secondsInAnHour = 3600;// 除以3600是把秒化成小时，除以60得到结果为相差的分钟数
NSInteger hoursBetweenDates = distanceBetweenDates / secondsInAnHour;
5、播放一张张连续的图片
// 加入现在有三张图片分别为animate_1、animate_2、animate_3
// 方法一
imageView.animationImages = @[[UIImage imageNamed:@"animate_1"],
[UIImage imageNamed:@"animate_2"],
[UIImage imageNamed:@"animate_3"]];
imageView.animationDuration = 1.0;
// 方法二
imageView.image = [UIImage animatedImageNamed:@"animate_" duration:1.0];
// 方法二解释下，这个方法会加载animate_为前缀的，后边0-1024，也就是animate_0、animate_1一直到animate_1024
6、防止离屏渲染为image添加圆角
// image分类
- (UIImage *)circleImage{
// NO代表透明
UIGraphicsBeginImageContextWithOptions(self.size, NO, 1);
// 获得上下文
CGContextRef ctx = UIGraphicsGetCurrentContext();
// 添加一个圆
CGRect rect = CGRectMake(0, 0, self.size.width, self.size.height);
// 方形变圆形
CGContextAddEllipseInRect(ctx, rect);
// 裁剪
CGContextClip(ctx);
// 将图片画上去
[self drawInRect:rect];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return image;
}
7、判断两个rect是否有交叉
if (CGRectIntersectsRect(rect1, rect2)) {}
8、将一个view保存为pdf格式
- (void)createPDFfromUIView:(UIView*)aView saveToDocumentsWithFileName:(NSString*)aFilename{
NSMutableData *pdfData = [NSMutableData data];
UIGraphicsBeginPDFContextToData(pdfData, aView.bounds, nil);
UIGraphicsBeginPDFPage();
CGContextRef pdfContext = UIGraphicsGetCurrentContext();
[aView.layer renderInContext:pdfContext];
UIGraphicsEndPDFContext();
NSArray* documentDirectories = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask,YES);
NSString* documentDirectory = [documentDirectories objectAtIndex:0];
NSString* documentDirectoryFilename = [documentDirectory stringByAppendingPathComponent:aFilename]; [pdfData writeToFile:documentDirectoryFilename atomically:YES]; NSLog(@"documentDirectoryFileName: %@",documentDirectoryFilename);}
9、保存UIImage到本地
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *filePath = [[paths objectAtIndex:0] stringByAppendingPathComponent:@"Image.png"];
[UIImagePNGRepresentation(image) writeToFile:filePath atomically:YES];
10、键盘上方增加工具栏
UIToolbar *keyboardDoneButtonView = [[UIToolbar alloc] init];
[keyboardDoneButtonView sizeToFit];
UIBarButtonItem *doneButton = [[UIBarButtonItem alloc] initWithTitle:@"Done" style:UIBarButtonItemStyleBordered target:self action:@selector(doneClicked:)];
[keyboardDoneButtonView setItems:[NSArray arrayWithObjects:doneButton, nil]];
txtField.inputAccessoryView = keyboardDoneButtonView;
11、在image上绘制文字并生成新的image
UIFont *font = [UIFont boldSystemFontOfSize:12];
UIGraphicsBeginImageContext(image.size);
[image drawInRect:CGRectMake(0,0,image.size.width,image.size.height)];
CGRect rect = CGRectMake(point.x, point.y, image.size.width, image.size.height);
[[UIColor whiteColor] set];
[text drawInRect:CGRectIntegral(rect) withFont:font];
UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
12、圆角矩形
- (void)drawRect:(CGRect)rect {
// Drawing code
/*画圆角矩形*/
float fw = 100;
float fh = 200;
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextMoveToPoint(context, fw, fh-4); // 开始坐标右边开始
CGContextAddArcToPoint(context, fw, fh, fw-4, fh, 4); // 右下角角度
CGContextAddArcToPoint(context, 100-16, fh, 100-16, fh-4, 4); // 左下角角度
CGContextAddArcToPoint(context, 100-16, 200-8, fw-4, 200-8, 4); // 左上角
CGContextAddArcToPoint(context, fw, 200-8, fw, fh-4, 4); // 右上角
CGContextClosePath(context);
CGContextDrawPath(context, kCGPathFillStroke); //根据坐标绘制路径
}
每隔4个字符添加一个空格的字符串算法
//每隔4个字符添加一个空格的字符串算法
- (NSString *)dealWithString:(NSString *)number
{
NSString *doneTitle = @"";
int count = 0;
for (int i = 0; i < number.length; i++) {
count++;
doneTitle = [doneTitle stringByAppendingString:[number substringWithRange:NSMakeRange(i, 1)]];
if (count == 4) {
doneTitle = [NSString stringWithFormat:@"%@ ", doneTitle];
count = 0;
}
}
NSLog(@"%@", doneTitle);
return doneTitle;
}
获取 UIAlertControll 中 TitleLabel 和 ContentLabel
UIView *subView1 = alert.view.subviews.firstObject;
UIView *subView2 = subView1.subviews.firstObject;
UIView *subView3 = subView2.subviews.firstObject;
UIView *subView4 = subView3.subviews.firstObject;
UIView *subView5 = subView4.subviews.firstObject;
//取title和message：
UILabel *titleLab = subView5.subviews[1];
UILabel *messageLab = subView5.subviews[2];
titleLab.wlAccessibilityLabel = titleLab.text;
messageLab.wlAccessibilityLabel = messageLab.text;
网友评论